Hsp90 is a family of proteins involved in many cellular functions, including the cellular defense against stress, the stability and function of mutated proteins, and the conformational maturation of key proteins involved in the growth response of cells to extracellular factors. In addition, Hsp90 has also been shown to be overexpressed in multiple tumor types and as a function of oncogenic transformation. Hsp90 inhibitors are therefore a highly pursued target in drug discovery efforts.
Radiolabeled Hsp90 inhibitors can be used clinically in a variety of applications related to treatment regimen, diagnosis, and patient monitoring. However, the currently available methods for placing a radioisotope on an Hsp90 inhibitor compound are prohibitively expensive due to poor yields and/or synthetic routes that sacrifice significant amounts of precious radioisotope.